An OLED device refers to such an electroluminescent device that is formed of an organic semiconductor material and a luminous material and is caused to emit light through injection and recombination of carriers upon it being driven by an electric field. OLED devices have many advantages and possess bright prospects in the field of display. OLED devices are very sensitive to water vapor and oxygen gas, and water vapor and oxygen gas that permeate into OLED devices are main factors that affect lifetime of the OLED devices. Water vapor and oxygen gas incur chemical reactions with the organic materials, leading to malfunction of the OLED device. For example, OLED devices belong to devices of a direct current (DC) driven type, and when an OLED device is in an operating state, a miniature electrolytic cell is produced inside the device if water vapor exists in the device, resulting in an electrochemical reaction. The produced reaction gas may separate a metal cathode from an organic function layer, leading to malfunction of the device.
Therefore, how to provide an encapsulation structure capable of preventing water vapor and oxygen gas from permeating into the OLED device is one of urgent technical problems to be solved.